Method of setting step and repeat machines.



UNITED STATES PA: 1ENT OFFICE.

HERBERT MORRIS PILKINGTON, 0F ARYERNE, NEW YORK, ASSIGNOR, BY MESNE ASSIGNMENTS, T0 LITHOTEZ CORPORATION, OF NEW YORK, N. Y., A CORPORATION OFVNEW YORK.

METHOD OF SETTING STEP AND REPEAT MACHINES.

No Drawing.

To all whom it may concern:

Be it known that I, HERBERT Monms PILKINGTON, a citizen of the United States, and a resident of Arverne, Long Island, county of Queens, and State of New York, have invented a certain new and useful Imfirovements in Methods of Setting Step and epeat Machines, of which the following is a specification.

This invention relates to a method of setting a step and repeat machine, and more particularly to the setting of a step and repeat machine for photographically reproducing a design formed on a photographic plate a number of times upon a larger plate or surface so that the reproductions of the design on said last surface shall register exactly with corresponding reproductions of the same design or a component design formed on a previously made photographic plate.

Thc invention is especially \iseful in forming plates for making multiple color prints, etc., where one plate for each color has to be made, each plate bearing a number of reproductions of the component unit for that color. In producing photographic plates for multiple color work in step and repeat machines, a separate unit photographic plate or object is made of that part of the design appearing in each of the different colors, and each unit plate is then put in the step and repeat machine and photographed a number of times on a separate large sensitized surface, preferably a glass plate, so as to produce a plate corresponding to each of the colors, each containing a number of reproductions of the unit design corresponding to the color which is to be printed from that plate or from printing surfaces made from that plate.

In order that the different colors will fall in their proper place in the completed print to give the desired registration, it is essentialthat the reproductions upon the different plates exactly coincide or register as to size and angular position, and in spacing from center to center of the different reproductions. In order that these requirements may be attained, the machine must have exactly the same setting in producing each of the plates corresponding to the dif- Speclflcation of Letters Patent.

Patented Mar. 9, 1915.

Application filed March 5, 1913. Serial No. 752,232.

ferent colors. If the unit for one color plate is of slightly dillerent size from the unit or units for the other color plate or plates, or if the focus of the machine has been changed so as to alter in the slightest degree the size of the projected image upon any of the plates to be produced,or if the position of the unit photographic plate or ob ect corresponding to any color has not been adjusted in its holder on the machine so that its projected images on the plate to be produced will have the same relative angular positions as the designs reproduced on the previously made plate corresponding to another color, or if the mechanism for moving the plate step by step past the lens and unit photographic plate has been disturbed since the previous plate was produced, the repro- (luction on the different plates will not register so as to have the component parts of the completed design properly match. It

is, therefore. very important for the opera-- tor to determine at the start, that the images of the designs corresponding to any particular color and about to be projected upon the plate will exactly coincide with the reproductions on a previously made plate corresponding to another color.

The present invention is for a method of ascertaining whether, or when, the apparatus is correctly adjusted for size and angular position of the image, or spacing of each design, or any two or more of these data combined, and it consists in placing a developed plate bearing reproductions of the same design or of a component design, in the plane to be occupied by the sensitized surface upon which it is desired to reproduce the unit design or object by means of the step and repeat machine, and projecting an image from the object plate from which the new series of designs is to be formed, onto one of the designs of said previously developed photographic plate with which the new design is to rcgistcn and adjusting the machine until the image exactly registers upon the said design on the plate; and if it is desired to check or rcget the machine for spacing the designs on the new plate, then shiftin; the plate :rans'vsse to the line of projection to bring the i nto aegis tration with the next adjagat disigz'i designs on the already developed plate to determine the necessary distance through which the plate must be stepped vertically or horizontally between exposures. The apparatus employed for producing these designs may be such as described in British Letters Patent No. 13517 of 1912 for step and repeat machine.

By my present 'invention, the operator may quickly and accurately determine what the actual adjustment of his machine is, as to size and angular position of the image and as to the spacing between the images to be projected. To do this he places the object or design to be reproduced in the ob- 'ect holder of the step and repeat machine ehind the lens, and places one of the photographic plates previously formed and developed (upon the carriage of the step and repeat machine for holding the sensitized plate which, is in front of the lens), in the 1 vertical plane to be occupied by the sensitized plate upon which the object or design now in the machine is to be reproduced, and then he projects the image from this object or unit design onto one of the corresponding designs of the previously made plate now on the plate carriage of the machine. If these exactly coincide, he knows his machine is properly set, and if there is not coincidence between the image and the already developed design, he can adjust the machine and readily see when the adjustment is such that precise registration occurs. This he does by shifting the focusing mechanism, fully set forth in the above-mentioned patent, so as to increase or decrease the size of the image of the design to be reproduced, and if it is found necessary to adjust the angular position of the image with respect to the design on the plate in order to make it coincide therewith, he only has to shift the unit desi holder as shown gn tical plane to be occupied by the sensitized in said specification, until the image thus projected coincides exactly with the developed design on the plate. If the op erator is uncertain about the adjustment of the mechanism for steppin the plate past the lens and unit design, a ter he has projected the image upon one of the developed designs so that they exactly coincide, he has only-to shift the large plate in its plane transverse to the lens until the image coincides with the next developed design on the plate irr the same horizontal row, whereupon, by the mechanism shown in the abovementioned specification, he notes the necessary movement to bring the image into registration with the second design on the plate, and if it is found that the movement does not correspond to his present setting of the machine, he adjusts his machine accordingly, and likewise for determining vertical stepping. The operator in this way can, before he commences the operation of reproducing solutely certain that the machine is properly the design upon the sensitized plate, be ab- Q adjusted for executing the second plate, and

and a holder for a sensitized late to be used for photographically repro ucing a component unit ofa multiple color design a number of times u on a sensitized surface to be used for making aprinting plate for one of the component colors of the design,

which consists in projecting an image of the unit transparency onto one' of the designs of an already made photographic late for one of the component colors of sai design, the plate being placed in the vertical plane to be occupied by the sensitized surface upon which the unit design is to be reproduced,

and adjusting the machine until the image exactly falls upon and coincides with sand design on the plate.

2. The method of setting a step and repeat machine embodying a lens, an object holder and a holder for a sensitized plate to be used for photographically reproducing a unit design a number of times upon a sensitized surface which is to be used for making prints of the design, each having a definite relation as *0 size, angular position and spacing, with designs formed upon a previously made plate, which consists in pro jecting an image of the unit design or object to be reproduced onto one of a number of corresponding designs 'on the already made photographic plate placed inthe versurface upon which the unit design is to be reproduced, and adjusting the machine until the image exactly falls upon or coincides with said design on the plate.

3. The method of setting a step and repeat machine embodying a lens, an object holder and a holder for a sensitized plate to be used for photographically reproducing a unit design a number of times upon a sensitized surface which is to be used for making prints of the design, each having a definite relation as to size, angular position and spacing, with designs formed upon a previously made plate, which .consists in projecting an image of the unit design or object to be reproduced onto one of a num ber 'of corresponding designs on the already made photographic plate placed in the vertical plane to be occupied by the sensitized surface upon which the unit design is to be reproduced, adjusting the machine until the image exactlyfalls upon or coincides with In testimony whereof, I have signed my said design on the plate, and then shifting name to this specification in the presence the plate transverse to the line of projection of two subscribing witnesses.

until the image falls upon and registers with HERBERT MORRIS PILKINGTON. another of said designs on the already made Witnesses: 1 plate, and noting the distance through which SAMUEL M. WARD, J12,

the plate was shifted. EDWIN SEGER. 

